Use problem globs to declare problem storage roots

[kiritofeng]

Also fixes #723

[codecov-commenter]

Codecov Report

Base: 81.44% // Head: 83.64% // Increases project coverage by +2.19% :tada:

Coverage data is based on head (b6195ae) compared to base (f31a0a7). Patch coverage: 49.25% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #728      +/-   ##
==========================================
+ Coverage   81.44%   83.64%   +2.19%     
==========================================
  Files         137      139       +2     
  Lines        4921     5032     +111     
==========================================
+ Hits         4008     4209     +201     
+ Misses        913      823      -90     

Impacted Files	Coverage Δ
dmoj/judgeenv.py	55.23% <19.51%> (-1.61%)	:arrow_down:
dmoj/monitor.py	36.55% <50.00%> (+0.68%)	:arrow_up:
dmoj/tests/test_glob_ext.py	100.00% <100.00%> (ø)
dmoj/utils/glob_ext.py	100.00% <100.00%> (ø)
dmoj/result.py	83.11% <0.00%> (-1.30%)	:arrow_down:
dmoj/executors/DART.py	100.00% <0.00%> (ø)
dmoj/executors/PIKE.py	100.00% <0.00%> (ø)
dmoj/executors/COFFEE.py	0.00% <0.00%> (ø)
dmoj/judge.py	54.54% <0.00%> (+1.21%)	:arrow_up:
dmoj/executors/java_executor.py	84.84% <0.00%> (+2.02%)	:arrow_up:
... and 6 more

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[Xyene]

This largely looks good to me. Could you update the PR description to include a sample config?

I'd like the next version we tag to be 3.0.0, since we have a fair number of breaking changes. So, I think we should:

• merge this PR
• queue up a PR totally removing the old config format, but not merge it until right before tagging 3.0.0 (so we don't wreck people installing from master)
• queue up a PR updating the docs

[kiritofeng]

As an example,

problem_storage_root:
- 2: /problems/ccc/nccc
- 1: /problems/apio
- 1: /problems/bbc

would become

problem_storage_globs:
- /problems/ccc/nccc/*/**/
- /problems/apio/*/apio*/
- /problems/bbc/*/bbc*/